The present invention relates to complexed metal salts, which will also be referred to as metal complexes in the following, which have at least one ligand and at least one complexing agent, wherein these complexed metal salts are particularly useful for chemically binding and adsorbing noxious and/or odour-producing substances, wherein particularly the ligands have a hydrophobic carbon skeleton with hydrophilic groups. The complexed metal salt formed with the complexing agent is advantageously soluble in water and surface-active. Preferred complexing agents are particularly water-soluble acids or salts of at least bifunctional acids, or also ether carboxylic acids.
The present invention also relates to the production of these complexed metal salts and their use as well as compounds that contain them.
It has long been known that zinc salts of fatty acids, which are also known as zinc soaps, have a de-odourising effect. A known example is the zinc salt of ricinoleic acid, zinc ricinoleate. These zinc salts are capable of chemically binding and thus neutralising the odour of substances such as nitrogen containing substances, which include the amines, or sulphur containing substances, such as thiols or mercaptans, as well as carboxylic acids, such as the strongly odorous compounds isovaleric acid and butyric acid. They are therefore particularly used in cosmetic and home care products.
However, the zinc salts of fatty acids, such as zinc ricinoleate, are insoluble in water, which is why until now it is has been necessary to create complicated formulations that enable the zinc salts to be converted to an aqueous solution or flowable concentrate. Examples of such are deodorants. These formulations are typically based on a large number of auxiliary materials, additives and/or solubilisers that together function as solubilising agents.
GB-PS 1 282 889 describes the use of zinc salts of unsaturated aliphatic hydroxycarboxylic acids having at least 17 C atoms, such as ricinoleic acid, for use as a deodorising medium.
A preparation with deodorising effect that contains the zinc salt of ricinoleic acid, amino-functional acids such as amino acids, solubilisers, organic and/or inorganic acids, and possibly water, is also known from the related art, for example from EP 1 319 394 A1. Tensides or glycols are used as solubilisers.
EP 1 250 938 A2 discloses a water-soluble homecare concentrate with zinc ricinoleate and an alkoxyamine derivative.
A deodorant described in EP 0 303 212 A2 is based on hydrolysed ene adducts and Diels-Alder adducts of ricin fatty acids and maleic anhydride, to which triethanol amine and an organic acid are added, and on a solvent from the alcohol group.
In DE 40 14 055 A1, a substance having deodorising effect is described that is based on the zinc salt of ricinoleic acid and/or the zinc salt of abietic acid and/or additional zinc salts of other saturated or unsaturated hydroxylated fatty acids having 16 and more C atoms, in which an ethoxylated fatty alcohol and a tertiary amine are also contained.
A large number of auxiliary materials and/or additives are needed, depending on the liquid or paste-like odour-adsorbing formulations of the related art, in order to transfer the water-insoluble zinc salts to these formulations.